Underwater wellhead assembly having passages closeable by a sleeve valve



June 13, 1967 T. A. BALMER ETAL. 3,324,951

UNDERWATER WELLHEAD ASSEMBLY HAVING PASSAGES OLOSEABLE BY A SLEEVE VALVE 5 Sheets-Sheet 1 Filed July 10, 1964 INVENTORS June 13, i6? T. A. BALMER ETAL 3,324,951

UNDERWATER WELLHEAD ASSEMBLY HAVING PASSAGES CLOSEABLE BY A SLEEVE VALVE 3 Sheets-Sheet 2 Filed July 10, 1964 W mJ Z I 6 my a 2W 5 INVENTORS June 13, 1957 F; ET 3,324,951

UNDERWATER WELLHEAD ASSEMBLY HAVING PASSAGES CLOSEABLE BY A SLEEVE VALVE 7 Filed July 10, 1964 6 Sheets-Sheet 5 0 36 5 a w. .i k l1 fl w 9 flaw 4% x f f IIIWIHHJI; \y X x INVENTOR-S United States Patent 3,324- 951 UNDERWATER WELLHEAD ASSEMBLY HAVING PASSAGES CLOSEABLE BY A SLEEVE VALVE Thomas A. Baimer, Lestan P. Normand, Jr., and Bobby G. Hurst, Beaumont, Tex., assignors to Gulf Coast Machine & npply Company, Beaumont, Tex., a corporation of Texas Filed July 10, 1964, Ser. No. 381,822 7 Claims. (Cl. 16687) This invention relates to wellhead structures and more particularly to a wellhead assembly specially adapted for wells drilled in submerged land locaitons.

In drilling wells in underwater locations, it is now becoming more and more the practive to locate the final wellhead assemblies immediately above the land bottoms so as to reduce the danger of collision by surface vessels and, in general, to protect them. However, setting and completing a wellhead assembly below the surface of a water body involves considerable difliculty and requires, in many instances, extensive use of divers who must physically descend to the underwater location and make up the parts constituting the wellhead.

Various designs and procedures are currently being developed by which the wellhead structures may be assembled from the surface, but these involve rather complex guide structures and manipulative procedures which are quite expensive and introduce numerous complications in their construction.

The present invention has for its principal object the provision of a relatively simple wellhead structure for mounting in submerged locations, which may be assembled largely by operations conducted from the surface of the water body and with a minimum of operations required to be performed by divers.

An important object is the provision of an underwater wellhead assembly made up of a casinghead and one or more tubingheads, depending upon the number of strings of pipe which are to be connected to the wellhead assembly.

A more specific object of the assembly is the provision of a structure in which the principal parts comprising the wellhead assembly are telescopically engageable and are secured together by means of spring-actuated latches whereby to enable the several major elements to be assembled and automatically secured to each other merely by relative longitudinal movement of the parts.

A further object is the provision, in a wellhead assem bly of the character described, of displacement passages for bypassing fluids through the structure at certain stages of assembly and of a sleeve valve arrangement for closing these passages at other appropriate stages during assembly of the wellhead structure.

Other and more specific objects and advantages of this invention will become more readily apparent from the following detailed description when read in conjunction with the accompanying drawing which illustrates a wellhead construction in accordance with this invention and several stages in its assembly.

In the drawings:

FIGS. 1, 2 and 3 are longitudinal, sectional views illustrating several stages in the assembly of the wellhead structure;

FIG. 4 is a vertical, sectional view of the final wellhead structure from which the various temporary manipulative elements have been removed;

FIG. 5 is a fragmentary, longitudinal view of a portion of the wellhead structure showing the position of the parts at closing of the sleeve valve over the displacement passages;

FIG. 6 is a fragmentary view in longitudinal section Patented June 13, 196'? showing a portion of the structure with the parts in the positions occupied in the final assembly; and

FIGS. 7 and 8 illustrate details of the latch elements employed in securing the tubingheads to the casinghead.

Referring first to FIG. 4, which shows the final assembly, there is shown the upper end of a well casing C which is the so-called surface or conductor pipe initially installed in a well bore W drilled into the land bottom B underlying a body of water H. The wellhead assembly in accordance with this invention is mounted on the upper end of casing C and comprises in ascending telescopically connected order, a casinghead, designated by the numeral 10, a first tubinghead, designated generally by the numeral 15, and a second tubinghead, designated generally by the numeral 24. Casinghead 10 includes an externally threaded tubular pin 11 extending from its lower end and adapted to be threadedly received in the upper end of casing C for securing the casin ghead to the casing. It will be under stood that instead of the screw connection illustrated, pin 11 may terminate in a conventional bolt flange for attachment in the known manner to a complementary flange provided on the upper end of casing C. Casinghead 10 has an enlarged axial bore 12 reduced slightly at a point near the lower end of the casinghead to define the bevelled internal shoulder 13 adapted to form a seat for first tubinghead 15, which is insertable into bore 12. The upper end of casinghead 10 is provided with an enlarged socket 16 having a section of coarse internal left-hand threads 17 for attachment thereto of a handling and operating casing string, as will be described subsequently. First tubinghead 15 has a lower portion 18 of a diameter to fit snugly in bore 12 and an upwardly extending section 19 of somewhat reduced diameter. First tubinghead 15 has an axial bore 29 extending therethrough, the lower end of which is adapted to receive the threaded end 21 of a tubing string T to serve as a hanger therefor. The upper end portion of bore 20 is enlarged to form a socket 22 defining at its lower end a bevelled shoulder 23 forming a seat for receiving second tubinghead 24.

First tubinghead 15 is provided with on or more generally longitudinal bypass or displacement passages 25 opening to the lower end of the tubinghead at one end and through the side of upward extension 19 at a point just above the upper end of lower section 18 which defines an annular shoulder 18a. Displacement passages 25 provide fluid communication between the interior of easing C and socket 16 exteriorly of tubinghead 15. A sleeve valve 26 is slidably mounted about the exterior of the lower portion of tubinghead extension 19 for movement from an upper passage-opening position above the upper ends of passages 25 (FIG. 2) to a lower position closing the latter, as best seen in FIGS. 3, 4, 5 and 6. Springloaded pins 27 are mounted in the exterior of extension 19 to project outwardly therefrom initially beneath the lower edge of valve 26 when the latter is in its uppermost position in order to retain the valve in the passage-opening position (FIG. 2). Pins 27 have rounded ends such that when downward pressure is applied to sleeve valve 26, the latter will be forced over the pins which will be forced inwardly allowing the sleeve valve to move down wardly to the position shown in FIGS. 3, 4, 5 and 6, clos ing passages 25, at which position the sleeve valve will be below the pins and the latter will be projected by the loading springs to extend over the upper the end of the sleeve valve and thereby retain it in its passage-closing position. Annular seals 28 are mounted in the exterior of extension 1? above and below the upper ends of passages 25 to seal with the inner face of sleeve valve 26 whereby to prevent leakage of fluid through passages 25 when the sleeve valve is in the closed position. The manner in which sleeve valve 26 is moved to the passage-closing position will be described subsequently.

Lower section 18 of first tubinghead 15 is provided with an annular upper seal 30 in its exterior surface for sealing with the wall of bore 12 of the casinghead. A bottom seal is provided between the lower end portion of section 18 and the wall of the casinghead and comprises an annular packing 31 seated in an annular recess 32 formed in the lower end of section 18. A metal gland or junk ring 33 is seated against the lower face of packing ring 31 and this packing assembly is secured in place by means of the studs 34 which extend through rings 33 and 31, and into the end of section 18. This packing assembly forms a seal between the lower portion of section 18 and the bore wall of the casing head when ring 33 engages on seat 13 in the casinghead and the packing ring 31 is compressed by the weight supported on tubinghead 15. The exterior of section 18 is provided with an annular groove 35 at a point between seal 30 and packing ring 31 and is adapted to receiv the outer ends of angularly spaced latch pins 36 which are slidably mounted in radial openings 37 extending through the wall of casinghead 10. Each latch pin 36 is biased outwardly of opening 37 by means of a coil spring 38, one end of which engages the inner end of the pin, the other end of the spring being seated in a recess provided in a cap 39 screwed into the outer end of opening 37. Two or more of the latch pins 36 will normally be employed and are illustrated in somewhat greater detail in FIG. 8. The upper edge of the outer end of latch pin 36 is bevelled at 40 so that when. tubinghead 15 is inserted in bore 12 of the casinghead, the .bevelled edge of gland ring 33 will engage the bevelled edges 40 of the latch pins and the reaction therebetween will thrust the latch pins inwardly of openings 37 sufliciently to allow the tubinghead to pass to the bottom of bore 12. Latch pins 36 are held against rotation by means of tapered pins 41 which are inserted through correspondingly shaped openings 42 in the bottom of casinghead socket 16 to project into longitudinal slots 43 provided in the upper faces of latch pins 36. As the lower end edges of latch pins 36 are cut square they will cooperate with the lower wall of groove 35 to prevent upward relative movement of tubinghead 15 once the latter is seated in the casinghead.

With the resiliently biased retractable latch pin arrangement provided in casinghead 10, as described, it will be seen that when tubinghead 15 is inserted into the bore of the casinghead far enough to project latches 36 into groove 35, the tubinghead will be locked automatically in place in the casinghead.

Tubinghead 15 is provided with an internally threaded radial opening 45 at a point just below socket 22 for attachment of an outlet pipe P. Before attachment of the latter and during assembly of the wellhead, opening 45 will be closed by means a of screw plug 46 (FIGS. 2, 3 and The exterior of the upper end portion of tubinghead extension 19 is provided with an elongate section of coarse left-hand threads 48, for purposes which will be described more fully hereinafter.

Second tubinghead 24 is provided in its lower end with an annular recess 50 in which is mounted annular packing 51 and a junk ring 52 engageable on seat 23 to compress packing 51 under the weight of tubinghead 24 and its supported load, and thereby form a lower seal between tubinghead 24 and the wall of socket 22 in tubinghead extension 19. Latch blocks 53, spring-loaded by springs 53a, are mounted in radial recesses 54 opening to the exterior of tubinghead 24 near its upper end and are projectible therefrom into an annular groove 55 formed in the wall of socket 22 which will be in registration with latch blocks 53 when tubinghead 24 is fully inserted in extension 19. (FIGS. 3, 4 and 6). The lower outer edges of latch blocks 53 are bevelled at 56 so that they will be forced inwardly and forced past the inner edge of the upper end of the wall of bore 22 when tubinghead 24 is inserted into socket 22. Stop pins 57 project upwardly from latch blocks 53 into elongate radial sockets 58 provided in the upper end of tubinghead 24 to permit limited .4 radial projection of the latch blocks while preventing dislodgrnent from the tubinghead. As in the case of tubinghead 15, it will be seen that tubinghead 24 is longitudinally slidably insertable in socket 22 and when fully inserted therein will be automatically locked therein by means of the latch blocks 53, the automatic latching action being effected by the relative longitudinal movement between the tubingheads. The upper edges of latch blocks 53 are cut square and will, therefore, shoulder against the upper end wall of groove 55 and prevent relative upward movement of tubinghead 24 once the latter is seated in bore 22.

Tubinghead 24 has an axial bore 60, the lower end of which is internally threaded to receive and form a hanger for a tubing string T which is smaller in diameter than tubing string T, and which will extend to a desired depth in the well. A nipple 61 may be threaded into the upper end of bore 60 and may, as shown, be provided with a control valve 62 for controlling flow of fluids from the well through tubing string T A circular cap 63 is positioned about nipple 61 and has an internally threaded lip 64 for connection to threads 48 at the upper end of tubinghead 15. Cap 63 also serves to hold tubing head 24 in place in socket 22 of tubinghead 15. A number of internally threaded vents 65 may be provided through the wall defining socket 22 for escape of gas during final assembly and are adapted to receive closure plugs 66. Annular seals 65a65a may be mounted in the exterior of tubinghead 24 at points above and below ports 65 to additionally seal against fluid leakage between the tubingheads.

Assembly of the wellhead structure is effected in several stages, some of which are illustrated in FIGS. 1, 2 and 3. Initially, as seen in FIG. 1, surface casing C will have casinghead 10 mounted thereon and the latter will be connected by means of a landing collar L to an operating casing 0 adapted to extend to the surface of the water body. Landing collar L is provided externally with coarse left-hand threads 70 complementary to threads 17 in the casinghead, being adapted to be released from the casinghead by a small number of rotations to the right. With the operating casing thus made-up to casinghead 10 and surface casing C, the latter will be inserted in bore W and cemented in place in the usual manner, the operations being conducted from the surface by conventional means through casing 0.

When surface casing C has thus been put in place, the second stage of operations, illustrated in FIG. 2, will be conducted. In this stage, a landing collar 75 having lefthand internal threads 76 matching threads 48 of first tubinghead 15 is connected to the lower end of an operating pipe string S and will be screwed down over thread section 48 a number of rotations to the left suflicient for the lower end of landing collar 75 to engage the upper end of sleeve valve 26. First tubinghead 15 and tubing string P, thus connected to operating string S, will be lowered through operating casing O and inserted into bore 12 of casinghead 10. When the lower end of tubinghead l5 lands on shoulder 13, latch pins 36 will automatically snap into groove 35, locking first tubinghead 15 in place in casinghead .10. With sleeve valve 26 in the upper position, as shown in FIG. 2, displacement passages 25 will be open allowing any fluids present in casing C to be displaced into the bore of operating casing 0, thereby allowing first tubinghead 15 and its connected string of tubing T to be lowered into casing C without interference. When this operation has been completed, landing collar 75 will be rotated to the left to screw it down over threads 48 a number of additional turns sufiicient to cause the landing collar to push sleeve valve 26 downwardly past pins 27 to the passageclosing position covering the upper ends of passages 25, this position being seen in FIGS. 3, 4, 5 and 6. When passages 25 have thus been closed, cementing of tubing string T may be effected through operating string S in the conventional manner in order to cement tubing string T in the well bore. 7

Upon completion of the last-mentioned cementing operation, operating string S and landing collar 75 will be disconnected from tubinghead 15 by rotating the string to the right. Threads 48 and 76 being left-hand threads, will permit landing collar 75 to be unscrewed from tubinghead 15 and permit operating string S to be withdrawn from operating casing O.

The next stage of operations is to land the second tubinghead 24 in place. The lower end of the latter will be connected to a string of tubing T and its upper end to nipple 61, control valve 62 and a landing nipple 80 (FIG. 6) by which the second tubinghead string is connected to a second landing collar 81 which may be connected to operating string S by replacing landing collar 75 thereon. When tubinghead 24 is set in socket 22, latch blocks 53 will automatically lock the second tubinghead to first tubinghead 15. The threads on landing nipple 80 being lefthanded, operating string S and landing collar 81 may be disconnected from landing nipple 80 by right-hand rotations and the operating string and landing collar Withdrawn from casing O.

Thereafter, operating casing O and landing collar L will be removed by rotating them to the right a sufficient number of turns to release the threaded connection between the landing collar and casinghead 10. Following removal of operating casing O, a diver will be employed to make the final connections by removing plug 46 and connecting a valved outlet pipe P in opening 45, inserting plugs 66 in ports 65, screwing cap 63 in place on the upper end of tubinghead extension 19' and, if desired, replacing landing nipple 80 by a pipe connection. When these underwater connections have been completed, the wellhead is ready for operation. Production may be taken either through pipe P or a pipe P connected to control valve 62 in place of landing nipple 80.

From the foregoing it will be seen that there is provided a wellhead assembly comprising a plurality of tubular wellhead fittings arranged in coaxial telescoped relation and provided with cooperating detent-type latch elements actuatable by the slidable insertion of one wellhead fitting into the next larger one to automatically lock the heads to each other.

It will be understood that in some instances only one production string may be necessary, in which case, second tubinghead 24 may be replaced by a suitable plug or solid cap adapted to close-off bore 29 above the point of connection of outlet pipe P.

It will be also understood that numerous changes and modifications may be made in the details of the illustrative embodiment within the scope of the appended claims but without departing from the spirit of this invention.

What we claim and desire to secure by Letters Patent 1. In a wellhead assembly including a tubular casinghead having an internal shoulder in the bore thereof, a tubular tubinghead slidable longitudinally into said bore to seat on said shoulder, cooperating latch means on said casinghead and tubinghead constructed and arranged to be operable automatically by insertion of said tubinghead into the casinghead bore to lock the tubinghead to the casinghead, fluid displacement passages extending through the tubinghead having lower ends opening through the lower end of the tubinghead and upper ends opening through the side thereof, sleeve valve means slidably mounted about the exterior of said tubinghead for movement longitudinally thereon relative to said upper ends of said passages between an upper passage-opening position and a lower passage-closing position, means removably positionable on the tubinghead for moving said sleeve valve means between said positions, and retractable means carried by the tubinghead for retaining said valve means in each of said positions.

2. In a wellhead assembly including a tubular casinghead having an internal shoulder in the bore thereof, a tubular tubinghead slidable longitudinally into said bore to seat on said shoulder, cooperating latch'means on said casinghead and tubinghead constructed and arranged to be operable automatically by insertion of said tubinghead into the casinghead bore to lock the tubinghead to the casinghead, fluid displacement passages extending through the tubinghead having lower ends opening through the lower end of the tubinghead and upper ends opening through the side thereof, sleeve valve means slidably mounted about the exterior of said tubinghead for movement longitudinally thereon relative to said upper ends of said passages between an upper passage-opening position and a lower passage-closing position means re movably positionable on the tubinghead for moving said sleeve valve means between said positions, and retractable lock means mounted in the exterior of the tubinghead positioned to cooperate with the upper and lower ends of said sleeve valve means to retain the latter in each of said positions upon attainment thereof.

3. In a wellhead assembly according to claim 2, annular seal means carried by the tubinghead and arranged to seal between the tubinghead and casinghead.

4. In a wellhead assembly, a tubular casinghead having an internal shoulder in the bore thereof, a first tubular tubinghead slidable longitudinally into said bore to seat on said shoulder, said first tubinghead having an internal shoulder in the bore thereof, a second tubular tubinghead slidable longitudinally into the bore of said first tubinghead to seat on the internal shoulder therein, cooperating first and second latch means arranged respectively between said casinghead and said first tubinghead and between said first and second tubingheads, each of said latch means being constructed and arranged to be operable automatically by insertion of the said tubingheads into the respective said bores to lock said tubingheads to each other and to said casinghead, fluid displacement passages extending through said first tubinghead having lower ends opening through the lower end thereof and upper ends opening through the side thereof, sleeve valve means slidably mounted about the exterior of said first tubinghead for movement longitudinally thereon relative to said upper ends of said passages between an upper passage-opening position and a lower passage-closing position, and means removably positionable on said first tubinghead for moving said sleeve valve means between said positions.

5. A wellhead assembly according to claim 4, wherein each of said latch means comprises spring-loaded detent elements and cooperating latching grooves disposed in the opposed concentric surfaces of the tubingheads and casinghead.

6. In a wellhead assembly according to claim 4, retractable lock pins mounted in the exterior of said first tubinghead positioned to cooperate with the upper and lower ends of said sleeve valve means to retain the latter in each of said positions upon attainment thereof.

7. An underwater wellhead assembly comprising a tubular casinghead having an internal shoulder in the bore thereof, means carried by the casinghead for attachment to a well casing, a section of left-hand threads in the bore of said casinghead above said shoulder for temporary attachment of an operating casing string, a first tubular tubinghead having an internal. shoulder in the bore thereof slidable longitudinally into the bore of the casinghead to seat on said shoulder, first latch means on said casinghead and first tubinghead constructed and arranged to be operable automatically by insertion of said first tubinghead into the casinghead bore to lock the first tubinghead to the casinghead, fluid displacement passages extending through said first tubinghead having lower ends opening through the lower end thereof and upper ends opening through the side thereof, sleeve valve means slidably mounted about the exterior of said first tubinghead for movement longitudinally thereon relative to said upper ends of said passages between an upper passage-opening position and a lower passage-closing position, means removably positionable on said first tubinghead for moving said sleeve valve means between said positions, retractable lock pins mounted in the exterior of said first tubinghead positioned to cooperate with the upper and lower ends of said sleeve valve means to retain the latter in each of said positions upon attainment thereof, a section of relatively coarse left-hand threads on the portion of the exterior of said first tubinghead extending above the upper ends of said sleeve valve means when the latter is in said upper passage-opening position, said last-mentioned threads being adapted for temporary attachment of an operating pipe string to said first tubinghead, a port through the wall of said first tubinghead for connection of a conduit, 9. second tubular tubinghead slidable longitudinally into the bore of said first tubinghead to seat on the shoulder therein, a second latch means on said first and second tubingheads constructed and arranged to be operable automatically by insertion of said second tubinghead into the bore of said first tubinghead to lock said second tubinghead to said first tubinghead, and means carried by said second tubinghead for temporary attachment of an operating pipe string, said tubingheads being adapted to support separate production pipe strings in concentric relation and extending through said casinghead into said well casing.

References, Cited UNITED STATES PATENTS 651,679 6/1900 Tait 16695 X 2,080,610 5/1937 Humason 16687 2,148,360 2/1939 Lemley 16688 2,531,942 11/1950 Lee 251343 2,700,982 2/1955 Fuentes et a1 251297 X 2,889,886 6/1959 Gould 166-89 3,171,489 3/1965 Cole et al. 16697 X 3,177,703 4/1965 Waters et a1. 166-0.6 X 3,273,646 9/1966 Walker 16686 CHARLES E. OCONNELL Primary Examiner.

ERNEST R. PURSER, Examiner.

I. A. CALVERT, Assistant Examiner. 

1. IN A WELLHEAD ASSEMBLY INCLUDING A TUBULAR CASINGHEAD HAVING AN INTERNAL SHOULDER IN THE BORE THEREOF, A TUBULAR TUBINGHEAD SLIDABLE LONGITUDINALLY INTO SAID BORE TO SEAT ON SAID SHOULDER, COOPERATING LATCH MEANS ON SAID CASINGHEAD AND TUBINGHEAD CONSTRUCTED AND ARRANGED TO THE OPERABLE AUTOMATICALLY BY INSERTION OF SAID TUBINGHEAD INTO THE CASINGHEAD BORE TO LOCK THE TUBINGHEAD TO THE CASINGHEAD, FLUID DISPLACEMENT PASSAGES EXTENDING THROUGH THE TUBINGHEAD HAVING LOWER ENDS OPENING THROUGH THE LOWER END OF THE TUBINGHEAD AND UPPER ENDS OPENING THROUGH THE SIDE THEREOF, SLEEVE VALVE MEANS SLIDABLY MOUNTED ABOUT THE EXTERIOR OF SAID TUBINGHEAD FOR MOVEMENT LONGITUDINALLY THEREON RELATIVE TO SAID UPPER ENDS OF SAID PASSAGES BETWEEN AN UPPER PASSAGE-OPENING POSITION AND A LOWER PASSAGE-CLOSING POSITION, MEANS REMOVABLY POSITIONABLE ON THE TUBINGHEAD FOR MOVING SAID SLEEVE VALVE MEANS BETWEEN SAID POSITIONS, AND RETRACTABLE MEANS CARRIED BY THE TUBINGHEAD FOR RETAINING SAID VALVE MEANS IN EACH OF SAID POSITIONS. 